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Republican presidential contender Ron Paul, fueled by an extraordinary Internet fundraising effort, hauled in more than $4.2 million in nearly 24 hours on Monday, a take that raised even the candidate's eyebrows

"It is amazing, it's even surprising to me, but it's of course very pleasant to know that people are spontaneously coming to us because it was not organized by the campaign. I have not yet talked to or met the individual that organized this, but yesterday's day's fundraising was all done on the Internet and it was all done spontaneously, so something significant must be going on out there in the countryside," Paul told FOX News Radio on Tuesday.

Paul, the Texas congressman with a libertarian tilt and an out-of-Iraq pitch, entered heady fundraising territory with a surge of Web-based giving tied to the commemoration of Guy Fawkes Day.

Fawkes was a British mercenary who failed in his attempt to kill King James I on Nov. 5, 1605. He also was the model for the protagonist in the movie "V for Vendetta." Paul backers motivated donors on the Internet with mashed-up clips of the film on the online video site YouTube as well as the Guy Fawkes Day refrain: "Remember, remember the 5th of November."

Paul advocates limited government and low taxes like other Republicans, but he stands alone as the only GOP presidential candidate opposed to the Iraq war. He also has opposed Bush administration security measures that he says encroach on civil liberties.

Paul said he thinks the people who are sending him money are independent voters disenchanted with Republican spending and the war in Iraq but "don't believe this Hillary (Clinton) stuff and (Barack) Obama, that they're going to stop the war ... because they really aren't. They're going to keep the troops there well into 2013."

He added that the audiences he meets are "upset with the war, they're upset with the economy, they're upset with the future. The young people don't look forward to paying into Social Security, and I come up with answers that are plausible and reasonable."

Paul's total is the highest amount raised by a candidate in one-day online fundraising. However, Mitt Romney is the single-day fundraising record holder in the Republican presidential field, having earned $6.7 million in one day of phone banks at the launch of his campaign. When it comes to sums amassed in one day, Paul now ranks only behind Democrats Hillary Rodham Clinton, who raised nearly $6.2 million on June 30, and Barack Obama.

Romney said Tuesday he was "delighted" with Paul's success.

"He's getting close to what I raised on our first day. ... so I am delighted that he's been able to raise what he needs to go forward, and it's only two-thirds as much or a little less than that than we raised on our first day," he said.

Paul spokesman Jesse Benton said the effort began independently about two months ago at the hands of Paul's backers. He said Paul picked up on the movement, mentioning in it speeches and interviews.

"It's been kind of building up virally," Benton said.

The $4.2 million represented online contributions from more than 37,000 donors, fundraising director Jonathan Bydlak said Monday night.

"Todays efforts surpassed John Kerry's record $2.7 million online fundraising efforts two days after the 2004 Super Tuesday primaries, and Republican John McCain's $1 million online following the New Hampshire primaries in 2000," the campaign said in a statement.

Paul has been lagging in the polls behind Republican front-runners. But he captured national attention at the end of September when he reported raising $5.2 million in three months, putting him fourth among Republican presidential candidates in fundraising for the quarter.

Paul has now raised more than $7 million since Oct. 1, more than half his goal of $12 million by the end of the year, according to his Web site.

Paul said the additional income will help his campaign step up operations in key primary states.

"We can buy unlimited TV in New Hampshire. We already had the 5 (million dollars) left over in the third quarter. So with this coming in, we can expand our purchases not only in New Hampshire, which is not expensive, but now South Carolina is more expensive. We'll be doing a lot more in Nevada and now the organizational work we need over in Iowa," he said.

FOX News Radio's Robyn Walensky and The Associated Press contributed to this report .